KR20050096454A - Array type multi-layer ceramic capacitor and the manufacturing process - Google Patents

Abstract

The present invention implements a variety of array-type multilayer ceramic capacitors (MLCCs), thereby minimizing the generation of internal stress by internal electrodes without affecting electrical properties. The present invention relates to an array type MLCC and a method of forming the same.

The present invention is a ceramic sheet; A plurality of internal electrodes printed on the ceramic sheet to form a predetermined circuit; A plurality of external terminals electrically connected to the internal electrodes; The ceramic sheet printed with the internal electrodes includes an MLCC in which internal electrodes are stacked such that wide and narrow widths are alternately formed at upper and lower layers thereof. The plurality of inner electrodes also provide an MLCC having at least one floating pattern between adjacent inner electrodes.

According to the present invention, there is an effect of improving the heat resistance of the chip while maintaining the electrical characteristics.

Description

Array Type Multi-Layer Ceramic Capacitor and the Manufacturing Process

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an array type multilayer ceramic capacitor (hereinafter referred to as MLCC) and a method of forming the same. More particularly, the present invention does not affect electrical characteristics by implementing various array patterns. The present invention relates to an array type MLCC and a method of forming the same, which can minimize generation of internal stress caused by internal electrodes.

In general, the manufacturing method of MLCC, first, an organic binder is added to a raw material powder such as BaTiO 3, MnO, Glass Frit, etc. to prepare a slurry, and the slurry is formed of a dielectric sheet into a ceramic sheet. Next, a patterned metal internal electrode of Ni, Cu, Pd, and Pd / Ag material is printed on the surface of the ceramic sheet, and a multilayer sheet is manufactured by laminating the ceramic sheet printed with the internal electrode in multiple layers. Compress at a pressure of 500 to 1300 kgf / cm 2. Then, the compressed laminated sheet is cut into a predetermined length to produce a rectangular parallelepiped ceramic gas, and then the ceramic gas is burned out in a firing furnace at a temperature of 230 to 350 ° C. for 20 to 40 hours, and a binder component is obtained. Removed and calcined for 10 hours to 24 hours at a temperature of 900 ~ 950 ℃ to 1100 ~ 1300 ℃. In addition, an external electrode is applied to the outer surface of the ceramic gas fired in the firing furnace, and then fired through a temperature and cooling step of 750 to 950 ° C. Finally, an external electrode is coated on the outer surface of the fired ceramic substrate, and then fired at a temperature of 750 to 950 ° C. for 30 minutes to 2 hours to form a terminal electrode, followed by plating to manufacture a product.

Recently, according to the trend of miniaturization and high functionalization of electronic products, chip components are also required to be miniaturized and highly functional, and in particular, an array type chip in which several terminals are connected in parallel to one chip is used.

In the case of MLCC, according to the above-mentioned miniaturization tendency, MLCC array is developed and mass-produced. The MLCC array consists of two or four MLCCs in one package. Each of these is commonly referred to as a two or four MLCC array (see FIG. 1). This structure not only has a high capacitance, but also can utilize a smaller area than when using a single chip, thereby miniaturizing electronic components by significantly reducing the mounting area.

As a chip component having a conventional array pattern, an MLCC having the same pattern has been proposed. This is illustrated in FIG. 2, which will be described below.

The MLCC includes a ceramic sheet 111, a plurality of internal electrodes 112 printed on the ceramic sheet 111, and forming a predetermined circuit, and a plurality of external terminals electrically connected to the internal electrodes 112. ) Is one of the chip components. Herein, the internal electrode 112 is printed to realize a constant capacitance. That is, internal electrodes having the same width W are formed.

Referring to FIGS. 3A and 3B, a conventional array type MLCC and a method of forming the same will be described.

First, a plurality of internal electrodes 112 forming a predetermined circuit are printed on all or part of the ceramic sheet 111, but the plurality of internal electrodes 112 are printed to have the same width W. FIG.

At least two ceramic sheets 111 on which the internal electrodes 112 are printed are vertically stacked and compressed, and then calcined and fired. In this case, the internal ceramics may be alternately stacked with the insulating ceramic sheets not printed.

Then, an external electrode (not shown) is applied to the edge of the multilayer ceramic chip 100 at regular intervals to form a terminal electrode.

As shown in FIG. 3B, the side cross-section along the line A-A 'of the conventional MLCC 100 stacked in the above manner is the same width (the inner electrode printed portion a on which the inner electrode 112 is printed). W) is aligned.

However, as shown in FIG. 3B, the same pattern of the internal electrode printed portion (a) and the unprinted portion (b) may be reduced due to a difference in plastic behavior in which the internal electrode printed portion (a) shrinks faster during the firing process. The internal stress is generated in the printing portion (b), so that it is weak in thermal shock or external impact, and thus there is a problem that cracks may occur vertically in the unprinted portion (b).

Therefore, there has been a need in the art for an array type MLCC and a method of forming the same which can prevent the above problems.

The present invention is to solve the conventional problems as described above, by providing a variety of array patterns to minimize the internal stress that may occur during the firing process of the internal electrode printed portion and the non-printed portion while preventing the crack phenomenon electrical characteristics An object of the present invention is to provide an array type MLCC and a method of forming the same, which can maintain the same.

The present invention to solve the above object is a ceramic sheet; A plurality of internal electrodes printed on the ceramic sheet to form a predetermined circuit; A plurality of external terminals electrically connected to the internal electrodes; The ceramic sheet printed with the internal electrodes includes an array type MLCC stacked in such a manner that the internal electrodes are alternately formed in the upper and lower layers thereof so that a wide width and a narrow width are alternately formed.

In this case, the plurality of inner electrodes are preferably printed such that the widths of adjacent inner electrodes are different from each other.

In addition, the present invention is a ceramic sheet; A plurality of internal electrodes printed on the ceramic sheet to form a predetermined circuit; A plurality of external terminals electrically connected to the internal electrodes; Wherein the plurality of internal electrodes provide an array type MLCC having at least one floating pattern between adjacent internal electrodes.

In addition, the present invention to solve the above object is a first step of printing a plurality of internal electrodes forming a predetermined circuit on all or part of the ceramic sheet; At least two ceramic sheets on which the internal electrodes are printed are vertically stacked, and the ceramic sheets are laminated and compressed to alternately form wide and narrow widths of the internal electrodes in upper and lower layers thereof, and then calcined and fired. Step 2; And forming a terminal electrode by applying an external electrode at regular intervals to an edge of the multilayer ceramic chip. It provides an array type MLCC forming method comprising a.

In this case, in the first step, the plurality of inner electrodes may be printed such that widths of adjacent inner electrodes are different from each other.

In addition, the present invention is a first step of printing a plurality of internal electrodes forming a predetermined circuit on all or part of the ceramic sheet, wherein at least one floating pattern is formed between the plurality of internal electrodes; A second step of vertically stacking and compressing at least two ceramic sheets printed with the internal electrodes and then calcining and firing; And forming a terminal electrode by applying an external electrode at regular intervals to an edge of the multilayer ceramic chip. It provides an array type MLCC forming method comprising a.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First embodiment

An array type MLCC and a method of forming the same according to a first embodiment of the present invention will be described with reference to FIGS. 4A and 4B.

In the MLCC 10 according to the present invention, a plurality of internal electrodes 12 forming a predetermined circuit on the ceramic sheet 11 are printed. The ceramic sheet on which the internal electrodes are printed is laminated so that the internal electrodes are alternately formed in the upper layer 11 and the lower layer 11 'such that a wide width W ″ and a narrow width W ′ are alternately formed. By dispersing the internal stress applied to the non-electrode non-printed portion consisting of only a weak ceramic sheet, it is possible to obtain an effect of increasing the resistance to thermal shock or external impact, as shown in the first embodiment. The inner electrodes may be printed such that the widths W ″ and W ′ of the adjacent inner electrodes are different from each other.

In this case as well, the ceramic sheet may be laminated so that internal electrodes are alternately formed with wide and narrow widths at upper and lower layers thereof. For this reason, after the ceramic sheets are stacked, the overlapping portions (corresponding to the narrow widths) of the internal electrodes are the same, and the wide width of the internal electrodes is not affected by the electrical characteristics of the conventional internal electrode unprinted portion b '. This will increase the resistance to external shocks.

The method of forming the array type MLCC according to the first embodiment of the present invention as described above is as follows.

First, a plurality of internal electrodes 12 forming a predetermined circuit on all or part of the ceramic sheet 11 are printed, wherein the plurality of internal electrodes 12 are the widths W 'and W of adjacent internal electrodes. It is preferable to print so that ") differs from each other.

At least two ceramic sheets 11 on which the internal electrodes 12 are printed are vertically stacked and compressed, and then calcined and fired. At this time, the ceramic sheet is preferably laminated so that the internal electrodes are alternately formed in the upper layer 11 and the lower layer 11 'such that a wide width W ″ and a narrow width W' are alternately formed. In order to minimize the conventional internal electrode non-printing portion (b ') consisting of only a weak strength ceramic sheet is aligned with the same width of the internal electrodes of, i.e., as shown in Figure 4b, the internal electrodes are alternately formed This is to disperse the internal stress applied to the conventional internal electrode unprinted portion b '.

Then, an external electrode (not shown) is applied to the edge of the MLCC 10 at regular intervals to form a terminal electrode.

The side cross-section of the MLCC 10 according to the present invention stacked in the above manner is shown in FIG. 4b, whereby the internal electrode 12 has a wide width (W ″) and a narrow width (W ′). It is formed repeatedly to reinforce the conventional internal electrode non-printing portion (b ') to increase the resistance in the case of external impact light.

Second embodiment

An array type MLCC and a method of forming the same according to a second embodiment of the present invention will be described with reference to FIGS. 5A and 5B.

In the MLCC 10 'according to the present invention, a plurality of internal electrodes 12 are formed on the ceramic sheet 11 to form a predetermined circuit, and the plurality of internal electrodes 12 are at least between adjacent internal electrodes. It is preferred to have one floating pattern 13.

It is provided with the floating pattern 13 to reinforce the internal electrode non-printed portion (b ") without affecting the electrical characteristics of the chip component to disperse the internal stress due to the plastic shrinkage behavior difference during the firing process to thermal shock or This is because the effect of increasing the resistance to external impact and the like can be obtained.

The method of forming the array type MLCC according to the second embodiment of the present invention as described above is as follows.

First, a plurality of internal electrodes 12 forming a predetermined circuit are printed on all or part of the ceramic sheet 11, and at least one floating pattern 13 is formed between the plurality of internal electrodes 12. . This is to reinforce the conventional internal electrode unprinted portion b "without affecting the electrical characteristics as described above.

At least two ceramic sheets 11 on which the internal electrodes 12 are printed are vertically stacked and compressed, and then calcined and fired. In this case, the internal ceramics may be alternately stacked with the insulating ceramic sheets not printed.

Then, an external electrode (not shown) is applied to the edge of the MLCC 10 'at regular intervals to form a terminal electrode.

The side cross-section of the MLCC 10 'according to the present invention stacked in the above manner is shown in Figure 5b, as can be seen by the floating pattern 13 formed between the internal electrode 12 as is known The internal electrode non-printed portion b ″ is reinforced to increase resistance in case of thermal shock or external impact.

Experimental Example

Hereinafter will be described the experimental process and results for determining the crack incidence of MLCC according to the present invention configured as described above.

(a) Conventional MLCC Preparation.

First, referring to FIGS. 3A and 3B, a plurality of internal electrodes 112 forming a predetermined circuit on all or part of the ceramic sheet 111 are printed to have the same width w.

At least two ceramic sheets 111 on which the internal electrodes 112 are printed are vertically stacked and compressed, and then calcined and fired. In this case, nickel paste was used as the internal electrode, and an external electrode (not shown) was applied at regular intervals, and a conventional MLCC was manufactured by plating.

(b) MLCCI preparation according to the present invention.

First, a plurality of internal electrodes 12 forming a predetermined circuit on all or part of the ceramic sheet 11 are printed with reference to FIGS. 4A and 4B, but the widths of the adjacent inner electrodes 12 are wide and narrow. The width W 'was printed so as to form repeatedly.

At least two ceramic sheets 11 on which the internal electrodes 12 were printed were vertically stacked and compressed, and then calcined and fired. At this time, in the lower ceramic sheet 11 ', the inner electrode is formed to repeat the narrow width W' and the wide width W " in turn, and in the upper ceramic sheet 11, the inner electrode has the wide width W. ") And narrow width (W ') were formed in order to repeat. In this case, the internal electrode was nickel paste (Ni paste) as in the conventional MLCC, and the external electrode (not shown) was applied at regular intervals and manufactured through a plating process.

(c) Preparation of MLCC II according to the present invention.

First, a plurality of internal electrodes 12 forming a predetermined circuit are printed on all or a part of the ceramic sheet 11 with reference to FIGS. 5A and 5B, and at least one floating pattern between the plurality of internal electrodes 12. (13) was printed to form.

At least two ceramic sheets 11 on which the internal electrodes 12 were printed were vertically stacked and compressed, and then calcined and fired. At this time, the internal electrode and the floating pattern 13 used a nickel paste (Ni paste), the external electrode (not shown) was applied at regular intervals and manufactured through a plating process.

(d) Experimental results.

The conventional MLCC prepared as described above, MLCC I and MLCC II according to the present invention was subjected to a lead heat test for 10 seconds in a 320 ° C lead bath. The results of analyzing the crack incidence in each MLCC after 10 seconds are shown in the following table.

TABLE 1

As shown in Table 1, the conventional MLCC is cracked in two chips out of 40, while the MLCC I and MLCC II according to the present invention did not generate any cracks. Accordingly, it can be seen that MLCC I and MLCC II according to the present invention have increased resistance to thermal shock or external shock by forming various array patterns.

The above has been described in detail with reference to the present invention, which is illustrative and does not limit the present invention.

The array type MLCC and the method of forming the same according to the present invention are dispersed by the internal stress generation due to the difference of plastic shrinkage behavior during the firing process of the inner electrode printed part and the unprinted part, It is effective to prevent the damage of MLCC.

In addition, according to the present invention, it is possible to prevent the internal electrode stacking misalignment caused by the high lamination and at the same time the overlapping portions of the internal electrodes are kept the same, thereby maintaining the electrical characteristics.

1 is a perspective view of a typical array type MLCC.

2 is an internal electrode pattern of a conventional array type MLCC.

3A is a process diagram of a conventional array type MLCC.

3B is a side cross-sectional view of a conventional array type MLCC.

4A is a process diagram of an array type MLCC according to the present invention.

Figure 4b is a side cross-sectional view of the array type MLCC according to the present invention.

5A is a process diagram of another array type MLCC in accordance with the present invention.

5B is a side cross-sectional view of another array type MLCC according to the present invention.

* Description of the symbols for the main parts of the drawings *

100 ... Conventional Array Type MLCC 111 ... Ceramic Sheet

112. Internal electrode a ... Internal electrode printed part

b, b ', b "... inner electrode unprinted part

10, 10 '... Array type MLCC according to the present invention

11, 11 '... ceramic sheet 12 ... internal electrodes

13 ... Floating pattern W, W ', W "... Internal electrode width

Claims (6)

Ceramic sheet; A plurality of internal electrodes printed on the ceramic sheet to form a predetermined circuit; And A plurality of external terminals electrically connected to the internal electrodes; Including, The ceramic sheet printed with the internal electrodes is an array type multi-layer ceramic capacitor (MLCC) stacked so that the inner electrode is formed alternately in the upper and lower layers of the wide and narrow width. The method of claim 1, And the plurality of inner electrodes are printed such that widths of adjacent inner electrodes in the ceramic sheet are different from each other. Ceramic sheet; A plurality of internal electrodes printed on the ceramic sheet to form a predetermined circuit; And A plurality of external terminals electrically connected to the internal electrodes; Including, And the plurality of inner electrodes have at least one floating pattern between adjacent inner electrodes. A first step of printing a plurality of internal electrodes forming a predetermined circuit on all or part of the ceramic sheet; At least two ceramic sheets on which the internal electrodes are printed are vertically stacked, and the ceramic sheets are laminated and compressed to alternately form wide and narrow widths of the internal electrodes at upper and lower layers thereof, and then calcined and fired. Step 2; And A third step of forming a terminal electrode by applying an external electrode at regular intervals to an edge of the multilayer ceramic chip; Array type MLCC forming method comprising a. The method of claim 4, wherein The method of claim 1, wherein the plurality of inner electrodes are printed such that widths of adjacent inner electrodes are different from each other. A first step of printing a plurality of internal electrodes forming a predetermined circuit on all or a part of the ceramic sheet, wherein at least one floating pattern is formed between the plurality of internal electrodes; A second step of vertically stacking and compressing at least two ceramic sheets printed with the internal electrodes and then calcining and firing; And A third step of forming a terminal electrode by applying an external electrode at regular intervals to an edge of the multilayer ceramic chip; Array type MLCC forming method comprising a.